Infusion systems are known which include a flexible bag as a fluid reservoir, a pump for pumping fluid from the bag to a patient, and a tubing from a bag to the pump and from the pump to the patient for transporting the fluid. Typically the bag is a flexible bag made from polymeric material, and the pump is an infusion-style pump designed to deliver a premeasured fluid drug dose at a given rate to the patient in need of the drug.
The bag may be hung from a pole or carried in an enclosure. Various enclosures are known including flexible pouches and more rigid enclosures. U.S. Pat. Nos. 5,540,561 and 5,567,119, the disclosures of which are incorporated herein by reference, concern rigid enclosure arrangements designed to protect fluid reservoirs. These enclosure arrangements include a chamber for receiving a fluid reservoir such as a flexible bag. The enclosures each include an opening for accessing the chamber. The enclosures each further include a latch arrangement for mounting an ambulatory pump to the enclosure to protect the reservoir and tubing.
These enclosures have a number of advantages as enumerated in U.S. Pat. Nos. 5,540,561 and 5,567,119. For example, flexible fluid reservoirs prepared from the polymeric materials are capable of being punctured or torn by sharp objects. This can be a problem for patients who use the pumps outside the hospital or caregiver's office. This creates a particular problem when the fluid contained within the bag is irritating to the skin or where the fluid contains a controlled substance. Where the fluid contained within the bag is a controlled substance, such as a narcotic, the enclosures prevent the controlled substance from being withdrawn from the bag by a needle punctured through the polymeric material or the tubing.
U.S. Pat. No. 5,879,143, the disclosure of which is herein incorporated by reference, concerns adapters designed to secure an infusion-type pump to an enclosure such that the enclosures discussed above may be used with a wide variety of pump sizes and shapes.
Many of the known flexible medical bags, for use in such infusion systems include outlet ports at their lower peripheral edge. Such arrangements may be problematic in that the enclosure arrangements used to protect the bags are sized to accommodate the peripheral space taken by the structure of the outlet port. Furthermore, the peripheral ports are more likely to present problems regarding occlusion. Often times, additional structure such as a bag post is included within the enclosure arrangement to hold the bag and thereby prevent the bag from laying on or otherwise occluding the fluid outlet port, or the tubing leading to the fluid outlet port.
There is a need for a flexible bag arrangement to address these concerns. It is desirable that the bag arrangement is usable within infusion systems having enclosure arrangements. It is also desirable that the bag arrangement allow for smaller enclosures in the enclosure arrangements, and that the bag provide for protection against occlusion without the need for additional structure within the enclosure arrangement.